Centrifugal concentrator



May 7, 1929. R. M. WENDEI. 3,712,134

CENTRIFUGAL CONCENTRATOR Filed Dec. 19, 1927 3 Sheets-Sheet 1 w. 3 5 2 22 Alg w QV Y 4 w V f l y Y. ,AJ i l l, Q,M% .W TH Mf 1 r m @o UHU I fX4. .nei y,

' mim@ i May 7, w29., R. M WENDEL.

CENTRIFUGAL CONCENTRATOR Fiied Dec. `19, 1927 3 Sheets-Sheet 2 -fica.14d 31a.

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INVENToR. /a m mm fe ATTORNEYS.

May 7, 1929. R. M. WENDEL.

n CENTRIFUGAL CONCENTRATOR Filed Dec. 19, 1927 5 Sheets-Sheet 3 32 42a43a. 254e gli! m. .N .maiz W Patented May 7, 1929,.

UNiTED STATES REINHOLD. M. WENDEL, OF AIGION, GREECE.

y cEN'rnmUGAL Application led December 19, 1927, Serial This inventionrelates to centrifugal machines for a mechanical concentrating of liquidmixtures or in fluids suspended solids. The invention is especiallyadapted for paper mills or factories and has for its main object toprovide a thoroughly ecient machine to recover the paper libres, whichusually are wasted with the escaping water. Without any. material changein its design the 11nproved machine, however, can be utilized for anyother class of manufacture where simllar conditions occur. A

Another object of the invention is the provision of a concentrator bywhich the concentrating process is combined with a lifting of themixture from a lower receptacle to a higher receptacle solely by meansof the cencontinuously carried out whereby also solids of a rather lightspecific gravity and mixed with a rather large quantity of the fluidvcan be readily recollected.

A still further obj ect of this invention is the provision of aconcentrating machlne in which the mixtureis caused to passy more thanvone concentrating device for the'purpose of treating mixturescontaining constltuents o rather dierent specific gravities.'

Further objects and advantages will appear in the following description.

For a full understanding of the invention and the merits thereof andalso to acquire a lmowledge of the details of construction and the meansfor effectingf the resultreference is to be had to the followingdescription and accompanying drawings, in which- Figure 1 is adiagrammatic sectional elevation of an embodiment of the invention withthree discharge passages for the constituents of the mixture;

Figure 2 is a similar view of another embodiment of the invention on asmaller scale but with the same arrangement of discharge passages; f iFigure 3 is a similar view of a third embodiment of the concentrator'with other kinds of centrator 1n Fig. 3, the pockets being inrectangular arrangement and the means controlfugal force which effectsthe concentration other way supported by discharge passages and withpocketlike pro- CONCENTRATOR.

N0. 241,236, and in Sweden October 7, 1926.

ling the discharge adjusted to different positions;

Figures 6-8 are plan views of the last mentioned embodiment in theconcentrator with pockets of variable numbers and forms;

Figure 9 is a sectional elevation of a fourth embodiment of theinvention;

' Figure 1() is a section of the last mentioned embodiment on a reducedscale and with the upper portions removed;

i-gure 11 is a sectional elevation of a further embodiment of theinvention, and

Figure 12a sectional view similar to Fig. 10 of the last mentionedembodiment.

Corresponding and similar parts are referred to in the followindescription and indicated-in all the views o the drawings by the samereference characters. The embodiments as well as their function aredescribed in the following in the sameorder as they are shown in 'thedrawings. y

In Fig. 1 the concentrator is shown as comprising a substantiallyconical drum l, the shaft 2 of which is vertical as are the shafts inall the other-embodiments. The end of the shaft 2 is supported by athrust bearing 3, and near-the top it is guided by a neck bearing 4,above which the shaft is provided with a pulley 5 driven from somesource of energy. The thrust bearingl 3 is integral with orin areceptacle or basin 6 wherein the mixture to be concentrated iscollected, and from which the mixture is to be lifted up to a receptacleon a higher level. The mixture to be treated in the following is assumedto -be the waste fluid from papermaking in which fibres and other solidconst ituents of the paper pulp are suspended.

The lower end 1 of the conical drum is submerged in the mixture in thelow level receptacle 6 and is providedwith an opening 7 for the entranceof the mixture into the drum.

v The top end 1" of the upwardly flared drum is open, and according tothe embodiments in Figs. 1 and 2 provided with either one funneloshapeddischarge distributer 9 (Fig. 2) or "J more than one such distributer 8and 9 (Fig.

1) telescopical therein. Said funnels preferably are adjustable axiallyfor instance by means of keys 10', 10" and 11', 11" respectively on theshaft 2, whereby the annular discharge passage 12 between drum 1 andfunnel 8, and the discharge passage 13 between the two funnels 8 and 9(Fig. 1) or the single mixture.

passage 120 between drum 1 and funnel 8 (Fig. 2) can be varied for thedischarge of variablequantities of the constituents of the The dischargepassages 12, 120 re spectively 13, 14 communicate with stationaryannular spaces or compartments 17 respectively 18, 19 separated fromeach other, and provided each with an outlet 20 respectively 21, 22. Theoutlet 20 communicates] outwardl with a collar 24 for the purpose -ofremovmg such fluid as may have adhered to the drum.

Stiiening arms 27 for the drum may be -of a shovel-like screw form so asnot to impede the rising movement of the mixture within the drum.

According to the embodiments shown in Figs. 3-8 the drum 1 along thecircumference is provided with radially projecting pockets 30"--30d ofany arbitrary number, but disposed' `symmetrically around the revolvingshaft 2 in order to maintain the stability of the machine when rotating.The pockets suitably are of such a form, that the circular cross sectionof the drum in Figs. 1 and 2 is substituted by a polygon with straightvor curved sides. The simplest embodiment is shown in Fig. 6 with twodiametrically opposed pockets 30, 30" which,viewed from above, form twoangles the sides of which make tangents to the circular section of thedrum. In Figs. 7 and 8 the pockets are three in number being the corners30a 30h and 30 of a triangular compartment with plane sides according toFig.' 7 and concave sides according to Fig. 8, the last mentioned shapefor the purpose of obtaining ratheracute angles, whichadvantagcouslyieets the result of the device. Figs. 4 and 5 show adesign with four pockets 30, 30", 30c and 30d forming a;

rectangle. The vertical sides 3131d of the pockets may in all theembodiments touch the greatest circumference of the drum, in order tofacilitate the centrifugal delivery of the concentrates into thepockets.

The drum and pockets are closed at the top by a cover 32 with a centralaperture 33 for the 'drum shaft 2. In the cover 32 swinging nozzles 34,34", 34 and 34d are provided a nozzle on the top of each pocket near thepoint of its angle. A number of discharge openings for instance two, 35,35", provided with radially vadjustable slides 36, 36", are disposednearer the centre line and communicate with pipes 37, 37 b withadjustable outlets The compartments 17, 18, 19,

not shown in the drawing, which pipes ex-V tend to the uppermostcompartment 19. The nozzles 3/il-34d end in the lowermost space 17,which-extends as near the centre line o the drum as possible. The numberof the 'discharge openings. ..35, 35" must suit the capacity of theconcentrator and the kind of iiuid to be treated therein.

The hitherto described substantially circular -drum 1 is in theembodiments in Figs. 9-12 substituted by a drum the cross section ofwhich shows a polygon with sharp or rounded corners which constitute theportions of the drum most remote from the centre line. In Figs. 10 and12 four such corners 30, 30, 30g, 301are shown, but the number isoptional andmust suitthe working and constructional-circumstances. Thecorners lie in the direction 'oftheproducerof the 'drum either along thewhole length thereof or alone its upper portion only, the last mentioneddesign being a transitional form from the pockets in Figs. 3-8. Vhilethe corners as well as the pockets are the portions of the drum mostremote from its centre line, they will be accumulating spaces for theconcentrates. As the concentration depends to a certain degree on thetime during which the mixture is exposed to the influence of thel mosteiiective centrifugal force, and as this time of influence on theotherhand depends on the axial length of the corners, it is easilyunderstood, that the axial length of the corners may be chosen accordingto the kind of mixtures to be treated.

Like the embodiment in Fig. 3 the concentrator drum in Fig. 9 is closedat the top by a cover 32 providedwith openings 35, 35 with radial slidesfor the discharge of the liquid which has been freed froln the'suspended solids, to the lower stationary collect- `ing compartment 19at the upper border of the drum. In the horizontal plane swingabledischarge nozzles 34e, Self, 34", 34 communicate with the otherstationary collecting compartment 17 positioned above the compartf ment19 (only'two collecting compartments are shown according to the simplestembodiment of the invention) for the collecting of the concentrates fromthe upper portions of each corner 30 30h respectively. The inlet 7 oftheconcentrator drum in this embodiment is so designed, that the mixture inthe low level receptacle 6 is pushed into the drum by the outer'staticpressure only without necessarily submerging the drum into the mixtureitself.

The embodiment shown in Figs. 11 and 12 is -a further development of theapparatus for continued concentrating of the contents. The concentratordrum .1 here is provided with an outer shell 40 of essentially the sameform as the single shell in Fig. 9, which in Fig. 11 constitutes theinner shell vand is designated by 39. Between the outer and inthefollowing.

during the-rotation of the drum are deprived of the heavier constituentsout to the outer drum 40. The cover 32 on the inner drum is extendedover the outer drumand in the corners vprovided with discharge nozzlesswingable in the horizontal plane viz in theoutermost-cornerspipemozzles 42, 42, 425,

42h for the concentrates and inside thereof nozzles 43, 43', 43g, 43hfor the separated liquid. The outermost nozzles 42 as well as thedischarge nozzles34 of the inner drum openinto the uppermost stationarycollecting compartment A17, and the inner nozzles 43 (as the openings 35of the single drum) discharge into the lower stationary collectingcompartment 19. If desired there is no ob- -`jection for a furtherdividingv of the discharged constituents for instance through theprovision of separate cllecting compart-` ments for the nozzles v42 and43. A

The operation of the different embodiments of the machine is to beclearly understood by The principle of the operation will appear mosteasily from Fig. 2. The noninterrupted Y upwardly llaring form of theconcentrator drum causes'the liquid which enters-the bottomopening 7 torise along the shell when it is thrown outwardl by the centrifugal force'against the shello the drum 1 and thereby brought to take part in therotation of-the latter. At the same time the mixture in a known mannerbecomes VTseparated, so that the heavier constituents V(the fibres ofthe waste pulp) are accumulated on the shell of the drum. When thus themixture is lifted to the upper border of the drum, the. concen- ,tratespass out through the annular passage 120 into the stationary compartment17 and l discharge through the outlet 20. The specific lighterconstituents which are held more remote from the shell ofthe drum flowover the lower edge 90 of the partition funnel 9, and discharge throughthe higher opemng 14 into the stationary com they escape throng theoutlet 22.

If the partition funnel 9 is moved axially upwards or downwards theannular passage 120 will be wider respectively narrower, so

that a thicker layer respectively a-thinner one is admitted throughsaidopening. Vari- .ous degrees of concentration of the mixturedischarge through the outlet isetected. Because of the essentiallyconical sha ofthe drum in combination with a suitab e speed ofrevolution the improved eoncentrator pro' cures the concentrating oflthemlxture as artment 19 from which velll as the lifting of the same toa desired eve It is diagrammatically shown in Fig. 1 how the risingmixture is divided into layers, so that the layer which is most rich insolid constituents will more closely approach the shell of' the drum,and the more the layersy of the mixture are remote from the shell thepoorer they are in fibres or other solid constituents, so that theinnermost layer 16 consists substantially in pure water Without anynoteworthy suspended solids. Naturally the layers-are not delined sodistinctly as indicated in the drawing but smoothly oating into eachother.A The layer 25 most rich in solids discharges at the top throughthe passage 12 into the compartment 17 and is carried by the pipe 20 tothe pulp tank not shown in the drawing. An intermediate layer 26containing less of solids is discharged through the annular passage 13between the two tunnels 6 and 9 into the compartment 18 and conductedback to the low 'level receptacle 6 by the pipe 21. At last theinnermost (water) layer 16 discharges through the innermost annularopening 14 to the compartment 19 whence it goes to the main drainchannel of the mill through the pipe 22. The percentage of fibres orother solids in the layers 25, 26 asl already mentioned is controlled bythe axial adjustment of the funnels 8, 9 by means of the keys 10', '10,11', 11". An adjustment upwardly'reduces .the concentration of thelayers 25, 26 and will at the same time increase the quantities'discharging into the compartments 17, 18.

As the layer 25 only has a degree of concentration suitable for the massin the pulp tank, onl this layer must he supplied to said tank. owever,it would he an undesirable waste of fibres, if the next layer 26, whichstill .is rather rich in fibres, would be allowed to escape through themain drain channel, and in order to avoidsuch a loss of material saidlayer is conducted back to the llow level receptacle 6 to pass theconcentrator once again together with 'the fresh quantity of wastemixture supplied `vdirectly from.` the paper-making wire. i

When the concentrator is used to recharge the waste libres into the pulptank the concentrator in many cases must be made comparably high,because the ulp tank always 1s disposed on a rather hig level above lthelow level receptacle 6. The revolving speed of the drum 1 as well as itsconic angle are to .be chosen in view thereof.

i the outlet openings. From the .pockets the concentrates are forced outthrough the swinging and comparably wide nozzles In the embodimentsshown in Figs. 3-8 the 34-34d into the compartment 17 from where morethe nozzles are swung inwards towards the centre line of the drum thegreater becomes the counteracting pressure caused therein by thecentrifugal force yand the thicker the concentration is. F ig. 4 showsthe position of the nozzles at a low degree of concentration and Fig. 5said position at a high degree thereof. Thus the variation of thepercentage of concentration here is not obtained by any variation ot'the Aoutlet area,

'and that brings with the great advantage,

that the outlets maintain the same Width un- -der all the circumstanceswhereby all risk of clogging is avoided also at the thickest degree ofconcentrations. The separated liquid escapes through the dischargeopenings 35, 35b in the cover and through the pipes 37a, 37b

-into the upper compartment 19 and thence through its outlet 22. Theposition at the slides 36, 36 as welll as the adjustment of thesectional areas of the pipes 37, 37b depend on the position of thesubstantially vertical surface of the centre cavity of the liquid withinthe drum 1 as well as of the desired degree of concentration.

In the embodiment according to Figs. 9 and 10 with an angularconcentrator drum the corners of said drum act as extended uf pocketswith the advantage of a highly increased degree of concentration. Thedouble or multiple device shown in Figs. 11 and 12 is especially adaptedfor such mixtures which contain solid constituents of very diferentspecific gravities. In such a case the lighter constituents wouldrequire such a high speed of revolution, that the heavier constituentswould stick to the shell of a single drum. The mixture to be treated inthis double or multiple drum enters through the bottom entrance 7 of theinner drum and is driven upwards by the' centrifugal force durino` therotation Whereat the 'angular' form olB the drum, beginning already nearthe entrance of the liquid, causesl a strong concentration as a resultof the heaviest concentrates accumulating in the longitudinal corners ofthe drum. This concentrate separated in the inner drum escapes at thetop thereof through the corner discharge nozzles 34 into the compartment17 and flows out from here,through the outlet 20. The mixture yetcontaining the lighter constituent at the top of the inner drum entersthe tubes 41 the ends of which are cut oblique, and the tubes conductsaid mixture to the lower portions of the outer drum 100, in which themixture again is submitted to lthe centrifugal force and moved upwardlywhereby on account of the larger radius of the outer drum va so muchstronger force'is set up than that in the inner drum, that also the Ilighter constituents are separated without necessity of such a highspeed of revolution that the heavier concentrates would be caused toadhere to the shell of the inner drum. The concentrates from the outerdrum escape through the outmost discharge nozzles 42 into the collectingcompartment 17, while the separated liquid Hows through the innerdischarge nozzles 43 of the outer drum into the collecting compartment19.

Thus the multiple device eHects a continued concentration of certainportions of the mixtures for somewhat the same purpose as that of thereconducting device in Fig. 1. The multipledevice also gives the sameresult at a low revolving speed of the drum lwhen treating a lightmaterial as does a single drum with a higher speed of revolution. Theoperation of the single drum without the outer drum as shown in Figs. 9and 10 is easy to understand from the above description without anyfurther explanation. It is evident,

that the more the corners of the drum are remote from the other portionsof the circumference of the drum, the higher degree of concentrationwill be obtained without increasing the revolving speed. The multipledevice naturally is not limited to a polygon concentral tor dru'm onlybut can be used with the same result also in the embodimentsshown inFigs.

. disclosed in the appended claims.

' Having thus described my lnventlon what I claim is 1. A centrifugalconcentrator for solids suspended in liquids comprising a verticallydisposed rotary drum of an essentially .cone like 'shape flaringupwardly along its entire length, a low level receptacle for the liquidmixture to be treated, and a high level receptacle for collectingv ofthe concentrate, the down end inlet of said drumsubmerging into the lowlevel receptacle, the drum surrounded by an outer drum of substantiallythe same form as said inner drum, both the drums provided with outletsfor constituents of various specific gravities, the outlets for theheaviest constituents communicating with the high level receptacle, andmeans to communicate the outer drum with the inner drum.A

2. A centrifugal concentrator for solids suspended 1n liquids comprisinga vertically disposed rotary drum of `an essentially cone like vsha peHaring upwardly along its entire length, a 10W level receptacle for theliquid mixture to be treated, and a high level receptacle for collectingof the concentrate, the down end inlet of said drum submerging into thelow level receptacle, the drum surrounded by an outer drum ofsubstantially the same fourni as said inner drum, both the' d rulnsprovided with outlets for constituents of various specific gravities,the outlets for the heaviest constituents connuunicatiug with the highlevel receptacle. and tubes communicating the lower portion of the outerdrum with the upper inner portions ot' the inner druin relatively nearthe centre line thereof.

3. A centrifugal concentrator for solids suspended in liquids comprisinga vertically disposed rotary drum of substantially cone shape, flaringupwardly along its entire length, a low level receptacle for'the liquidmixture to be treated, and ahigh level receptacle for, collecting theconcentrate, the lower inlet end of said drum being submerged in the lowlevel receptacle, the drum being provided With lateral pockets formingnarrow corners, said pockets being provided with outlets extendinginwardly from said corners, the drinn being provided with outlets forthe heaviest constituents communicating with the high level receptacleas well as outlets for the other constituents of the mixture.

4. A centrifugal coneentrator for solids suspended in liquids comprisinga vertically disposed rotary drum of substantially cone like shapeflaring upwardly along its entire length, a low level receptaclev forthe liquid mixture to be treated, and a high level receptacle forcollecting the concentrate, the lower inlet end of said drum beingsubmerged in the low level receptacle, the drum being provided Withlaterally projecting pockets forming cornersin their outmost portion andprovided with outlets for the heaviest constitu- 'ents communicatingwith the high level receptacle, and means to adjust the outflow of saidoutlets, said means including nozzles adapted to be swung in ahorizontal plane to vary the position of their outlet ends with respectto the center of said drum.

nature. l

REINHOLD M. WENDEL.

In testimony whereof I have axed my sigim

